US Copper Corp Announces Positive Results from Superior Drill Program
October 18, 2021 at 06:28 pm EDT
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US Copper Corp. announced positive results from the first 5 diamond drill holes of 7 completed holes drilled on its Superior deposit at the Moonlight-Superior Copper Project in Plumas County, North-East California. The objective for US Copper's current drill program is to verify 50-year-old drill results (96 drill holes ("dh") totaling 50,000 feet ("ft") which will enable recalculation of the current resource (Tanaka, 2014) and the reclassification of most of the resource from inferred to indicated. With sufficient data a further objective would be to include silver and gold values in the resource. Ultimately, US Copper intends to include the updated Superior resource into a revised Moonlight PEA (TetraTech, 2018) which was based on only the nearby Moonlight Deposit. The historic drilling by Placer Amex was done on a 250 ft x 250 ft grid of vertical holes averaging <600 ft per dh. Little documentation and Quality Assurance/Quality Control (QAQC) protocols were retained limiting the resource classification to inferred. US Copper's full program as previously announced will drill 10 - 12 vertical and angle holes (10,000 ft) inside the historic grid. Some holes will twin older holes while most will be interior to the grid pattern. Assay results from the other two completed drill holes are still pending and will be reported later. All seven completed holes were drilled entirely in the quartz monzonite of the mid-Jurassic Lights Creek Stock. Mineralization consists of high-grade chalcopyrite with minor bornite and other copper sulfides in tourmaline-magnetite veins and veinlets (21.9 ft of 1.1% Cu in S21-1; 15.6 ft of 1.27% Cu in S21-4). Lower-grade disseminated mineralization is widespread adjacent to and between the vein-veinlets. The average grade of the total footage (3,598 ft) from the five holes reported here is 0.2% copper, which exceeds the cutoff grade used in the Moonlight PEA (2018). No significant oxide copper occurs at Superior, and pyrite is minor. The drill program at Superior and Engels was initially designed to be a seven-hole program to confirm historic Placer assays and test for gold/silver credits that had not been thoroughly measured previously. With a successful financing in the spring, USCU decided to expand the program to complete 10 - 12 holes at Superior (plus another three holes at Engels) for the purpose of upgrading the existing inferred resource (Tanaka, 2014) to the indicated category and then potentially rolling the Superior resource into an updated Moonlight PEA (TetraTech, 2018). The Dixie Fire over-ran the project area in September requiring the evacuation of employees, contractors, and the drill crew, prematurely terminating this season's program. Between 1915 and 1930, underground mining methods extracted approximately 4.7 million tons of ore producing 160 million lbs. of copper averaging 2.2% copper, plus silver and gold credits from the Superior and nearby Engels deposits. Most of the production came from Engels, with less than 1 million tons coming from several 5 - 20 ft wide moderately dipping structures at Superior. During the 1960's Placer recognized lower grade, potentially open-pitable mineralization, between and surrounding these structures and drilled 96 vertical surface holes (totaling about 50,000 ft) on a 250 ft. square grid. They defined a resource which they estimated at of 72 million tons ("mt") of 0.384% Cu using a 0.25% cutoff. US Copper (formerly Crown Mining Corp) released a new resource (Tanaka, 2014) estimating an Inferred resource of 60 mt containing 0.41% Cu with a 0.2% cutoff. The lack of complete documentation from Placer's earlier work precluded an Indicated classification of the resource. Because of insufficient data neither of these resource estimates included silver or gold values. US Copper personnel regularly observe procedures including the boxing of core at the drill site. Core is then securely delivered to the core logging and storage facility in Crescent Mills CA (~10 miles from the drill sites). The core is logged, magnetically scanned, and photographed. Periodic samples are collected for specific gravity testing and petrographic analysis. The core is then sawn in half. One half is bagged with appropriate documentation and securely transported to the ALS lab in Reno, NV. To ensure that proper QAQC accompanies the analyses appropriate QAQC elements are included in each batch of samples. The QAQC elements consist of certified standards, duplicate analyses and certified coarse blanks or blank material that has been documented to be barren for gold and base metals.
US Copper Corp. is a Canada-based exploration stage company. The Company has interests in exploration properties in Ontario, Canada and, through wholly owned subsidiaries, has interests in exploration properties in Nevada and California, United States. It controls approximately 13 square miles of patented and unpatented federal mining claims in the Lightâs Creek Copper District in Plumas County, NE California; essentially, the entire District. The District contains substantial copper (silver) sulfide and copper oxide resources in three deposits, such as Moonlight, Superior and Engels, as well as several partially tested and untested exploration targets. The Moonlight deposit hosts a current National Instrument 43-101 (NI 43-101) indicated resource of approximately 252 million tons. The Superior Project includes about 132 unpatented mining claims and a lease on 36 patented claims in Plumas County, California. It also owns mining interests in Timore, Warren Whiteside, and Black Warrior.